When Should You Not Eat Mayonnaise?

According to the USDA, opened mayonnaise should not be left at room temperature for more than two hours, a critical safety rule to prevent bacterial growth. So, when should you not eat mayonnaise? This creamy condiment poses risks when spoiled, mishandled, or consumed in excess due to its high fat and calorie content.

Quick Summary

This guide outlines crucial times to avoid eating mayonnaise, including when it shows signs of spoilage, is left unrefrigerated for too long, or is homemade with raw eggs. It also covers health considerations like high fat and calories, as well as preventing contamination to ensure food safety.

Key Points

• Spoilage is a major concern: Discard mayonnaise immediately if you notice mold, a putrid smell, or a separated, watery texture.

• Follow the two-hour rule: Never leave opened mayonnaise at room temperature for more than two hours to prevent dangerous bacterial growth.

• Be cautious with homemade versions: Homemade mayonnaise made with raw eggs carries a higher risk of salmonella and should be consumed within a few days.

• Refrigerate promptly after opening: Once a commercial jar is opened, it must be stored in the refrigerator and consumed within one to two months.

• Use clean utensils: Prevent cross-contamination by always using a clean spoon or knife to serve mayonnaise, especially after handling raw meat.

• Watch your calorie intake: Due to its high fat and calorie content, mayo should be consumed in moderation, especially if you are managing your weight.

Know the Signs of Spoilage

One of the most important reasons to avoid mayonnaise is when it has gone bad. Spoiled mayonnaise can cause foodborne illness, so it's essential to check for signs of spoilage before consuming.

Look for these tell-tale signs:

• Visible mold: The presence of any green, black, or white mold is an absolute sign to throw it out immediately.
• Off odor: A fresh jar of mayo has a subtle, tangy aroma. If you detect a strong, acidic, or putrid smell, the mayonnaise is spoiled.
• Color change: Discoloration, such as a shift from its typical off-white to a darker yellow or brownish hue, indicates spoilage.
• Texture changes: Separation of the oil, a watery consistency, or a lumpy texture are all red flags that the emulsion has broken down.
• Off taste: If all other signs are absent, a bitter, sour, or strange taste is a final confirmation that the product is no longer safe to eat.

Understanding the Dangers of Improper Storage

Proper storage is crucial for both store-bought and homemade mayonnaise. Mishandling is a primary cause of spoilage and can lead to dangerous bacterial growth.

How to avoid storage-related issues:

• The Two-Hour Rule: Perishable foods, including those made with mayo, should never be left at room temperature for more than two hours. This is especially important for things like potato salad at a picnic. The risk increases significantly in warm weather.
• Immediate Refrigeration: As soon as you open a jar of commercial mayonnaise, it must be refrigerated. Keep the lid tightly sealed to minimize air exposure, which causes flavor deterioration and encourages bacteria.
• Homemade Mayo Risk: Homemade mayonnaise, often made with unpasteurized raw eggs, has a much shorter shelf life. It should be consumed within a few days to minimize the risk of salmonella contamination.
• Avoid Cross-Contamination: Always use a clean utensil to scoop mayonnaise from the jar. Double-dipping or using a knife that has touched raw meat can introduce harmful bacteria.

Health Considerations and Concerns

Beyond spoilage, there are several health-related scenarios where you might choose to avoid or limit your intake of mayonnaise.

High in Calories and Fat

Mayonnaise is a calorie-dense condiment. Just one tablespoon can contain 90-100 calories and a high amount of fat. For individuals monitoring their caloric intake or trying to lose weight, excessive consumption can easily derail their goals.

Potential for Allergies

Since traditional mayonnaise is made with eggs, individuals with egg allergies must avoid it. Vegan or eggless mayonnaise alternatives are widely available for those with this dietary restriction.

Vulnerable Individuals

Pregnant women, young children, the elderly, and those with compromised immune systems should be particularly cautious. The risk of salmonella from raw-egg homemade mayonnaise is a serious concern for these groups.

Comparison Table: Homemade vs. Store-Bought Mayonnaise

Feature	Homemade Mayonnaise	Store-Bought Mayonnaise
Shelf Life	Very short (3-7 days refrigerated)	Longer (up to 2 months after opening)
Egg Safety	Higher risk of Salmonella if unpasteurized eggs are used	Eggs are typically pasteurized, significantly reducing risk
Preservatives	None, which explains the short shelf life	Contains preservatives to extend shelf life
Flavor	Fresh and customizable, but can go rancid quickly	Consistent and stable flavor due to manufacturing process
Fat/Calorie Content	Highly variable depending on ingredients	Often high in fat and calories, with lighter options available
Storage	Needs constant and careful refrigeration	Requires refrigeration after opening; shelf-stable beforehand

Conclusion

Knowing when to avoid mayonnaise is essential for maintaining food safety and promoting good health. The primary reasons include spoilage, improper storage, and high-calorie content. Always check for signs of spoilage such as off odors, color changes, or mold. Adhering to the two-hour rule for refrigeration and using clean utensils are critical steps in preventing contamination. While commercially produced mayonnaise is relatively safe due to pasteurization and preservatives, homemade versions pose a higher risk of bacterial illness, especially when made with raw eggs. For those concerned with fat and calorie intake, moderation is key. By understanding these risks, consumers can make informed decisions and enjoy this condiment safely.

Frequently Asked Questions

Can I eat mayonnaise after its 'best by' date?

For safety reasons, it is not recommended to eat mayonnaise, particularly opened jars, significantly past the 'best by' date, as the risk of bacterial growth increases over time. Trust your senses to check for signs of spoilage.

What are the signs that mayonnaise has gone bad?

Signs of bad mayonnaise include visible mold, a strong acidic or putrid odor, a change in color (dark yellow or brownish), a watery or lumpy texture, or an 'off' taste.

Is mayonnaise the actual cause of food poisoning from a picnic salad?

Contrary to a common myth, commercially produced mayonnaise is highly acidic and actually inhibits bacterial growth. Food poisoning from dishes like potato salad is more often caused by other ingredients like potatoes or eggs becoming contaminated and left at unsafe temperatures.

How long can mayonnaise be left out of the fridge?

The USDA recommends that opened mayonnaise not be left out at room temperature for more than two hours. The risk increases if the temperature is warm.

Is it safe to make and eat homemade mayonnaise?

Homemade mayonnaise is safe if made with pasteurized eggs and handled properly, but has a very short refrigerated shelf life of a few days. Using unpasteurized eggs increases the risk of salmonella and is not recommended, especially for vulnerable individuals.

Does freezing mayonnaise work to extend its shelf life?

No, freezing mayonnaise is not recommended. The process causes the emulsion to break, leading to separation and an undesirable texture when thawed.

What are some healthier alternatives to mayonnaise?

For a lighter option, consider alternatives like Greek yogurt, mashed avocado, or mustard. These can provide a creamy texture with fewer calories and fat.